I recommend social hobbies. Mine are BJJ and Magic the Gathering. BJJ is great because it can be highly technical but you will meet people way outside of nerd circles. My kids do it and love it as well. It is a hard thing, too, so it keeps the ego in check. You have no choice but to be extremely, intimately close with other humans. The friends I am making are great. There are plenty of other hobbies, but start there.
Seconded. I've been training Brazilian jiu jitsu for 15 years. For most of that time, friends from jiu jitsu has been half of my social life. When I graduated and moved to a new area by myself for a job, jiu jitsu is how I met people.
Brazilian jiu jitsu is correct. It’s a wrestling style.
Compared to many martial arts, BJJ is very interactive in that you learn something new and then immediately put it into practice against training partners. BJJ gyms don’t really do katas (lining up the class to practice poses/moves individually).
This is nice because you get immediate feedback on what works. I’m a small guy. In a real fight I would probably get smashed by any average sized dude, but my experience diving into jiu jitsu has been fun and interesting. It’s a very technique based and strategic game, so my size isn’t as much of a factor as it would be in other sports.
Most gyms do a free trial period. You won’t have any idea what you’re doing for the first month or two, but I think it’s healthy to get humbled once in a while.
California (specifically So Cal) is kind of the Mecca of BJJ in the US, so a gym should be easy to find. Give it a try everyone.
SoCal is not just the Mecca of BJJ in the US, I think it has become the Mecca of BJJ in the world. IBJJF Worlds has been held in Long Beach, CA since 2007. (And was last weekend!)
But, I also submit that the NY area is the central place for jiu jitsu on the US east coast.
Edit: (start by investigating social hobbies)